This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Ground-level ozone (O3), an important oxidant component of urban air pollution, has been consistently linked to excess respiratory and lung disease in epidemiological studies. Chronic exposure to O3 may be associated with restructuring of the lung with increased cell proliferation. Epithelial-to-mesenchymal transition (EMT), a key embryological process and also central to wound healing, has been implicated in lung fibrosis disorders and may play a role in cancer progression. EMT is promoted in oxidative-stressed cells. The primary objective of this research, therefore, is to investigate whether ozone exposure may induce EMT in lung cell lines.